Network Troubleshooting or Is there any hope my Performance will be seen over the network

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Network Troubleshooting or Is there any hope
my Performance will be seen over the network?

• Bob Riddle Technologist
• January 2005

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What is a network geek doing at a New World
Symphony seminar?

• Did I come to share my musical talents?
• I played the bassoon in elementary school
  middle school
• I taught myself to play a guitar, I now play it 1
  week a year
• My kids gave me a harmonica want to hear me
  play?
• No? then lets look at some network stuff
• using the network to stretch the stage the
  auditorium
• the kind of tools you need in your network
  toolbox?
• how to stack the deck in your favor

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Issues to consider when stretching the stage
the auditorium
Things to think about when stretching the
stage

• Speed do you need a freeway, city street, or a
  dirt road? (H.323 HDTV)
• Latency is it a telephone call or a movie?
  (streaming or interactive)
• Packet Loss is there any junk mail you can
  throw away?

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Issues to considerDo you need a dirt road or a
freeway?

• Determine the quality of the Experience
• Mpeg1 1.5 3.0 mpbs
• H.323 384 1.5 mbps kbps
• Mpeg2 4 15 mbps
• DV 30 mbps
• HDTV 20 270 mbps 1.5 gbps
• Determine the type of Experience
• One way? (streaming, broadcast)
• Two way? (interactive voice, video)
• Many way? (more than 2 end points)
• Do the Math check your onramp!

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Issues to consider unicast or multicast

• cant I get away with just unicast? (Real, QT)
• Depends on the road 384 kbps or 30 mbps
  stream(s)
• i.e. stats from earlier Victoria Secrets webcast
• More than 1 million web hits during 1st hour
• 283 increase in web traffic during event
• Unicast delivery doesnt cheaply scale!
• think of multicast as Broadcast TV
• If you have a tuner and your antenna is
  pointed in the right direction, just tune in the
  channel
• If youre on a Internet2 backbone, youre ready!
  (well, almost ready )
• Do the math (stream potential endpoints)
• If theres only 1 endpoint, use unicast
• If its a Victoria Secrets type thing, use
  multicast

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If the math works out then go for a test
drive

• Take a good look at your local roads
• Run internal tests across your LAN
• Make sure youre testing what you plan to use!
• Find a friend next door to test with
• Learn about ping, traceroute, the Detective,
  ethereal, iperf, DVTS, VLC what they can tell
  you about your network situation
• Start thinking about the on-ramp, the freeway,
  and those other local roads at your endpoints
  and potential endpoints

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Network Toolbox Basic tools

• Ping can I get from here to there?
• History of Ping
• Web Page with Ping other tools
• Spend 24.95 for pretty pictures
• Beware! ICMP packets are now often blocked
• traceroute (tracert) what roads do I travel
• Web Page with Ping other tools
• Spend 24.95 for pretty pictures
• When things good one direction but not the other,
  check for asymmetrical routes (then check for
  full duplex trouble!)

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Network Toolbox more tools

• Internet2 Detective
• check your on-ramp to Abilene
• test your multicast capability
• Test your speed (bandwidth)
• Check you speed from here to there using iperf
• Another detective
• SurfNet NAT, firewall tests, duplex test, IPv6
  test, etc.

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Network Toolbox more tools

• check out your network capability
• DVTS/DVGuide readily available streams
• MPEG2 example (using VLC client)
• Research Channel 233.0.73.28
• University of Washington 233.0.73.29
• DVTS example (using DVTS WinXP client)
• Research Channel 233.0.73.25
• University of Pennsylvania 233.0.55.10
• University of South Florida 233.22.29.128
• Internet2 Test Channel 233.45.17.50

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Network Toolbox great tools

• ethereal look at the traffic on your road
• Powerful Multi-Platform Analysis
• Useful for checking TTL, determining whether its
  a network problem or an endpoint problem
• iperf bandwidth measurement tool
• Peer-to-peer tool for performance testing
• Supports tcp, udp, multicast traffic
• Supports uni-directional bi-directional testing
• Mailing lists
• bigvideo_at_internet2.edu
• wg-multicast_at_internet2.edu

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Stack the deck in your favor

• Use an early-warning system!
• Wouldnt it be nice if you could figure out if
  there was any hope your stuff would work without
  having to buy/borrow/steal another expensive
  device to ship to each end point?
• Wouldnt it be nice if you could use a cheap PC
  to determine if there was any hope?
• Wouldnt it be nice if you could use free (or
  almost free!) software to determine if there was
  any hope?
• Think about building cakeboxes

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Stack the deck using the cakebox

• Criteria for the cakebox
• Small, inexpensive, easy to ship device
• No operator, no monitor, keyboard, or mouse
  required
• Just plug in a network cable a power cable
• Provide web interface for non-network geeks
• http//envoy.internet2.edu/pioneer/
• What it will allow you to do
• Allows representative bandwidth testing
• Shows you what road youll travel
• Allows you to exercise broadcast (multicast)
  traffic
• You can find out if there is any hope

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Stack the deck using the cakebox

• Cakebox built using freely available tools
• http//dast.nlanr.net/Projects/Iperf/
• http//dast.nlanr.net/Projects/Beacon/
• http//dast.nlanr.net/NPMT/
• Packaged on Linux Platform
• phone-home to LDAP server
• Secure access via SSL to web server
• Secure access via SSH directly to cakebox

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